This section provides background information related to the present disclosure and is not necessarily prior art.
Selective catalytic reduction technology has been used in conjunction with reducing nitrogen oxides present in the exhaust of combustion engines. Many vehicles utilizing combustion engines are equipped with exhaust aftertreatment devices for reducing nitrogen oxide emissions. Some of these systems are constructed using urea-based technology including a container for storing the urea and a delivery system for transmitting the urea from the container to the exhaust stream. While these systems may have performed well in the past, it may be desirable to provide an air-assisted delivery system to more efficiently and effectively deliver the urea (or other reductant) to the exhaust stream. Furthermore, it may be desirable to purge the delivery system with water and/or air to maintain the efficiency and effectiveness of delivery system.